The English Vowels

Definitions of Vowels:

“Vowel is a speech sound in which the mouth is open and the tongue is not touching the top of the mouth, the teeth, etc”. (Oxford Learner’s Dictionary).

“Vowel is a speech sound produced by humans when the breath flows out through the mouth without being blocked by the teeth, tongue, or lips”. (Cambridge Learner’s Dictionary). 

Vowels are described by the IPA using the three dimensions of:

1. Height

The height of a vowel refers to the position of the mandible (open or close), or it can also refers to the vertical position of the tongue towards the palatal area (low or high).

Generally, there are four variations use to define vowel height. They are:

open, open-mid, close-mid, and close.

In addition, we will see on vowel chart, several vowels are not clearly defined using the height labels. In order to provide clear and descriptive labels for all vowels, phoneticians have agreed on the use of the terms “near-open” and “near-close” to describe the additional vowels.

2. Frontness

Frontness refers to the horizontal position of the tongue in relation to the front or back of the mouth.

The three variations of frontness are front, central, and back.

Similar with the height dimensions, several vowels which are not clearly defined using the particular labels (in this case, the frontness labels), will use the terms “near-front” and “near-back” on the chart to describe the additional vowels.

3. Rounding

Rounding refers to the position of the lips during the production of the vowel.

The two lip positions are rounded and unrounded.

IPA Vowels Chart:

In the Oxford English Dictionary (OED) which is appointed as an English dictionary for standard of BBC pronunciation, some particular symbols are changed. In this case, the tense vowels (the vowels require tension in selected muscles for production and are long in duration), followed by colon ( : );

Besides, there is also an additional symbol, such as (/i/) for the pronunciation of particular words; and.
The symbol of open-mid front unrounded vowel (/ℇ/) is also changed.

The Explanation of Vowels Presentation Format:

Similar with consonants, for the purposes of clarity and consistency of the parameters of vowel sounds, generally, it can be determined sequentially based on the three aspects of vowels:

Describe the sound based on the height;

Describe the sound based on the frontness; and

Describe the sound based on the rounding.       

Thus, to make a sound parameter of /u:/ for example, we can describe it as follow: 

                “/u:/ is a close (high) back rounded sound”.